Paper separation mechanism

ABSTRACT

A paper separation mechanism applied to an office machine is disclosed. The paper separation mechanism comprises a roller set driven by a drive motor, a gear set disposed on a side of the roller set, and an adjusting device disposed on a side of the gear set for providing a resistant torque. Thereby when the roller set is driven by the drive motor and a thrust provided by the drive motor overcomes the resistant torque, the roller set starts to feed paper.

FIELD OF THE INVENTION

The present invention relates to a paper separation mechanism, and more particularly to a paper separation mechanism applied to an auto document feeder (ADF).

BACKGROUND OF THE INVENTION

With the progress of the electronic technology, most office works rely on functions of the copy machine, the fax machine, the printer, and the scanner, etc., and such office machines become indispensable equipments in the office. Since these office machines occupy lots of space and have different using rates, a multi-function peripheral (MFP) having multiple functions of copying, faxing, printing and scanning in one structural unit is thus developed to conform to the trends of miniaturization and function integration. Therefore, the consumer can only buy one multi-function peripheral for performing multiple office works, so that the occupied space is decreased and the working quality and efficiency are improved.

Both the single-function peripheral and the multi-function peripheral have a paper feeding mechanism and a paper separation mechanism, so as to feed paper sheets (such as the originals) placed on the tray into the image processing unit of the peripheral to be further copied, faxed, printed or scanned. The paper sheets are separated and fed into the peripheral sheet by sheet by means of the friction force between the pickup roller and the separation pad and the normal force provided by the spring disposed under the separation pad, so as to prevent the problems of paper jam or multiple feeding.

Please refer to FIG. 1, which is a schematic view showing the conventional paper separation mechanism. As shown in FIG. 1, the conventional paper separation mechanism 1 comprises a pickup roller 11, a separation pad 12, a spring 13, an adjusting component 14 and a drive motor 15. The pickup roller 11 is driven by another driving device (not shown). Parts of the separation pad 12 contact with the pickup roller 11 where the paper sheet is fed into the peripheral. The lower end of the separation pad 12 is connected to the upper end of the spring 13, and the other end of the spring 13 is installed on the adjusting component 14, which is driven by the drive motor 15. The spring 13 provides an upward normal force; when the paper feeding mechanism is turned on and the pickup roller 11 starts to rotate, the pickup roller 11 picks up the uppermost paper sheet and the second uppermost paper sheet is blocked out of the pickup roller 11 via the friction force between the pickup roller 11 and the separation pad 12 to prevent the multiple feeding. However, although such design can prevent the problem of multiple feeding, the lifespan of the peripheral is shortened due to the frictional wear between the pickup roller 11 and the separation pad 12 and the heavy load of the drive motor.

Therefore, it is required to provide an improved paper separation mechanism to overcome the defects of the above described prior art.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a paper separation mechanism, which employs the resistant torque provided by the adjusting device to reduce the feeding torque provided by the roller set, and the roller set starts feeding paper after the thrust provided by the drive motor overcomes the resistant torque. Accordingly, the friction between the roller set and the separation pad can be decreased to reduce the frictional wear and prolong the lifespan of the roller set and the separation pad.

According to an aspect of the present invention, there is provided a paper separation mechanism. The paper separation mechanism comprises a roller set driven by a drive motor, a gear set disposed on a side of the roller set, and an adjusting device disposed on a side of the gear set for providing a resistant torque. Thereby when the roller set is driven by the drive motor and a thrust provided by the drive motor overcomes the resistant torque, the roller set starts to feed paper.

In an embodiment, the roller set comprises a first roller and a second roller.

In an embodiment, the gear set comprises a first gear, a second gear, and a third gear. Preferably, the first gear is disposed on a side of the first roller, the third gear is disposed on a side of the second roller, and the second gear is meshed between the first gear and the third gear.

In an embodiment, when the thrust provided by the drive motor has not overcome the resistant torque yet, the roller set rotates downwardly till the roller set contacts the paper.

Preferably, the paper separation mechanism further comprising a protruding shaft disposed on a sidewall of the roller set for receiving the adjusting device. The adjusting device comprises a resilient component, a friction disc, and a friction plate. For example, the resilient component is a spring.

In some embodiments, the paper separation mechanism is applied to a copy machine, a fax machine, a printer, a scanner or a multi-function peripheral.

According to another aspect of the present invention, there is provided a paper separation mechanism. The paper separation mechanism comprises a roller set comprising a first roller and a second roller, wherein the first roller is driven by a drive motor; a gear set comprising a first gear, a second gear, and a third gear, wherein the first gear is disposed on a side of the first roller, the third gear is disposed on a side of the second roller, and the second gear is meshed between the first gear and the third gear; and an adjusting device disposed on a side of the second gear for providing a resistant torque. Thereby when the first roller is driven by the drive motor and a thrust provided by the drive motor overcomes the resistant torque, the first gear drives rotations of the second gear and the third gear and further drives the second roller to roll in the same direction as that of the first roller.

In an embodiment, when the thrust provided by the drive motor for driving the first gear has not overcome the resistant torque yet, the roller set rotates downwardly till the second roller contacts the paper.

In an embodiment, when the thrust provided by the drive motor for driving the first gear has overcome the resistant torque, the second roller rolls in the same direction as that of the first roller to feed the paper.

The above objects and advantages of the present invention will become more readily apparent to those ordinarily skilled in the art after reviewing the following detailed description and accompanying drawings, in which:

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view showing the conventional paper separation mechanism;

FIG. 2 is a schematic view showing the paper separation mechanism according to the preferred embodiment of the present invention; and

FIG. 3 is a schematic view showing the adjusting device of the paper separation mechanism according to the preferred embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The present invention will now be described more specifically with reference to the following embodiments. It is to be noted that the following descriptions of preferred embodiments of this invention are presented herein for purpose of illustration and description only; it is not intended to be exhaustive or to be limited to the precise form disclosed.

Please refer to FIG. 2, which is a schematic view showing the paper separation mechanism according to the preferred embodiment of the present invention. The paper separation mechanism 2 is applied to an office machine, such as a copy machine, a fax machine, a printer, a scanner or a multi-function peripheral. As shown in FIG. 2, the paper separation mechanism 2 comprises a roller set 21, a gear set 22 and an adjusting device 23. The roller set 21 comprises a first roller 211 and a second roller 212, and the first roller 21 is driven by the drive motor (not shown) through the transmission shaft 24. The gear set 22 comprises a first gear 221, a second gear 222, and a third gear 223, wherein the first gear 221 is disposed on a side of the first roller 211, the third gear 223 is disposed on a side of the second roller 212, and the second gear 222 is an idle gear meshed between the first gear 221 and the third gear 223, so that when the first gear 221 is rotated, the third gear 223 can also be rotated through the transmission of the second gear 222. In addition, the adjusting device 23 is disposed on a side of the second gear 222 and provides a resistant torque.

When the drive motor begins driving the first roller 211 to rotate the first gear 221 and the first roller 211 simultaneously, the second gear 222 and the third gear 223 cannot be rotated since the adjusting device 23 provides the resistant torque. In the meantime, the whole roller set 21 rotates downwardly till the second roller 212 contacts the paper sheet (not shown). When the thrust provided by the drive motor overcomes the resistant torque provided by the adjusting device 23, the first gear 221 has sufficient torque to drive rotations of the second gear 222 and the third gear 223 meshed with the second gear 222, so the second roller 212 can roll in the same direction as that of the first roller 211, and thus, the uppermost paper sheet can be easily delivered into the paper feeding mechanism. After the feeding demand disappears, the drive motor provides a reverse driving torque, so that the whole roller set 21 will rotate upwardly and the second roller 212 will be lifted and apart from the surface of the paper sheet to stop the paper delivery.

Please refer to FIG. 3, which is a schematic view showing the adjusting device of the paper separation mechanism according to the preferred embodiment of the present invention. As shown in FIG. 3, the adjusting device 23 comprises a resilient component 231, a friction disc 232 and a friction plate 233. A protruding shaft 25 is disposed on a sidewall 213 of the roller set 23, and the resilient component 231 (such as a spring), the friction disc 232 and the friction plate 233 are sequentially sleeved on the protruding shaft 25, and then, the second gear 222 is fixed at the end of the protruding shaft 25. Via the normal force provided by the resilient component 231, the friction disc 232 will apply a force on the friction plate 233 to provide the resistant torque (also named friction torque). Certainly, the adjusting device 23 can be made with various modifications, but not limited to the embodiment shown in FIG. 3. For example, the relative positions, the amounts or the types of the resilient component 231, the friction disc 232 and the friction plate 233 can be modified, and also, the position, the shape or the material of the protruding shaft 25 can be changed according to the design of the paper separation mechanism.

Certainly, the position and the amount of the gear set 22 are not limited to the disclosed embodiment, and the amount of the adjusting device 23 can be increased in response to various requirements, and the adjusting device 23 is not limited to be only disposed on the second gear 222. For example, the adjusting device 23 can be additionally disposed on a side of the third gear 223.

In conclusion, according to the preferred embodiment of the present invention, the paper separation mechanism employs the resistant torque provided by the adjusting device to reduce the feeding torque provided by the roller set, so that when the first roller of the roller set is driven by the drive motor, the roller set rotates downwardly to enable the second roller to contact the paper sheet. After the feeding torque provided by the drive motor overcomes the resistant torque provided by the adjusting device, the roller set starts feeding paper with the cooperation of the first, second and third gears. Accordingly, the friction between the roller set and the separation pad can be decreased to reduce the frictional wear and prolong the lifespan of the roller set and the separation pad. Therefore, the paper separation mechanism of the present invention possesses industrial value.

While the invention has been described in terms of what is presently considered to be the most practical and preferred embodiments, it is to be understood that the invention needs not be limited to the disclosed embodiment. On the contrary, it is intended to cover various modifications and similar arrangements included within the spirit and scope of the appended claims which are to be accorded with the broadest interpretation so as to encompass all such modifications and similar structures. 

1. A paper separation mechanism comprising: a roller set driven by a drive motor; a gear set disposed on a side of said roller set; and an adjusting device disposed on a side of said gear set for providing a resistant torque; thereby when said roller set is driven by said drive motor and a thrust provided by said drive motor overcomes said resistant torque, said roller set starts to feed paper.
 2. The paper separation mechanism according to claim 1 wherein said roller set comprises a first roller and a second roller.
 3. The paper separation mechanism according to claim 1 wherein said gear set comprises a first gear, a second gear, and a third gear.
 4. The paper separation mechanism according to claims 2 and 3 wherein said first gear is disposed on a side of said first roller, said third gear is disposed on a side of said second roller, and said second gear is meshed between said first gear and said third gear.
 5. The paper separation mechanism according to claim 1 wherein when said thrust provided by said drive motor has not overcome said resistant torque yet, said roller set rotates downwardly till said roller set contacts said paper.
 6. The paper separation mechanism according to claim 1 further comprising a protruding shaft disposed on a sidewall of said roller set for receiving said adjusting device.
 7. The paper separation mechanism according to claim 1 wherein said adjusting device comprises a resilient component, a friction disc, and a friction plate.
 8. The paper separation mechanism according to claim 7 wherein said resilient component is a spring.
 9. The paper separation mechanism according to claim 1 being applied to a copy machine, a fax machine, a printer, a scanner or a multi-function peripheral.
 10. A paper separation mechanism comprising: a roller set comprising a first roller and a second roller, wherein said first roller is driven by a drive motor; a gear set comprising a first gear, a second gear, and a third gear, wherein said first gear is disposed on a side of said first roller, said third gear is disposed on a side of said second roller, and said second gear is meshed between said first gear and said third gear; and an adjusting device disposed on a side of said second gear for providing a resistant torque; thereby when said first roller is driven by said drive motor and a thrust provided by said drive motor overcomes said resistant torque, said first gear drives rotations of said second gear and said third gear and further drives said second roller to roll in the same direction as that of said first roller.
 11. The paper separation mechanism according to claim 10 being applied to a copy machine, a fax machine, a printer, a scanner or a multi-function peripheral.
 12. The paper separation mechanism according to claim 10 when said thrust provided by said drive motor for driving said first gear has not overcome said resistant torque yet, said roller set rotates downwardly till said second roller contacts said paper.
 13. The paper separation mechanism according to claim 12 wherein when said thrust provided by said drive motor for driving said first gear has overcome said resistant torque, said second roller rolls in the same direction as that of said first roller to feed said paper.
 14. The paper separation mechanism according to claim 10 further comprising a protruding shaft disposed on a sidewall of said roller set for receiving said adjusting device.
 15. The paper separation mechanism according to claim 10 wherein said adjusting device comprises a resilient component, a friction disc, and a friction plate.
 16. The paper separation mechanism according to claim 15 wherein said resilient component is a spring. 